Support



Nov. 28, 1933.

J. K. WOOD SUPPORT Filed Feb. l, 193s e sheets-sheet 1 J. K. WOOD Nov.28, 1933. i

SUPPORT 6 'sheets-sheet 2 Filed Feb. 1,. 1935 Sam W INVENTOR JasfPH YE DAT1-o EY Nov. 2s, 19.33.l Y J. K. woon SUPPORT Filed Feb. 1. 1933 esneetsheef 5 INVNTOR U NN m fast-PH /IAy B ff AT1-o NEY J. vK. WoonSUPPORT Filedk Feb, 1, 1933 R Y o E .v0.m.\, en@ klem. Aww M \/r 5a u Ey r//a m m A JsfP/f /ey /1/000 Nov. 28, 1933.

:tha: r l EL Nay. 28, 1933.

J. K. woon 1,937,135

SUPPORT `Filed Feb. 1. 1933 6 sheets-sheet 5.

Nov. 28, 1933.

J. K. WOOD SUPPORT Filed`Feb-. l. 1933 6 Sheets-Sheet 6 Patented i Nov.28, 1933 UNITED STATES f SUPPQRT Joseph Kaye Wood,

signor to General Mount Vernon, N. Y., as-

Spring Gorporaton, New

York, N. Y., a corporation ofNew York Application February 1, 1933.Serial No. 654,63

` 22 claims. (61.'248531) This invention relates to a support whichpermits movement of its load for a substantial distance along its lineof pull, while affording to said load an approximately constantsupporting force.

More particularly, the invention relates to a spring support such, forexample, as is described and claimed inmy Patent No. 1,816,164, dated A.July 28, 1931, in which the moments of the weight of the load and thepull of the spring upon a pivoted member are adjusted relative to oneanother, so thatthe force applied to the load is more nearly constantthan in the device illustrated and described in my said prior patent.

In my prior patent above referred to, I have '15 described and claimed asupport or hanger in which a movement of the load is accommodated bymeans of a spring, and the variation in tension of the spring whenextended or contracted is compensated for by means of a pivoted lever.

.20 To this end, the lever is so mounted that the change in the momentarm (i. e., the perpendicular distance from the line of` action of theforce to the pivot of said lever) at which the spring acts on the levervaries, e. g., due to the rotation of z5 the lever about its pivot, soas to compensate at leastl partially for the increase or decrease intension of the spring when distorted or relaxed. As set forth in my saidpatent, complete compensation is not secured by the preferredembodimentdescribed therein, and there remains a small variation in theforce with which the load is supported, e. g., between five and ten percent 0f the Weight of the load.

It is an object of the present invention to re- .25 duce or eliminateentirely the variation in' the force applied to the load. It is a.further object of the invention to provide means for adjusting theforce applied to the load in "any position without interfering with theconstancy of the applied force in the various `positions for which thedevice is designed. A further object of the invention is so to designthe hanger that the range of operation will always fall within therangeof maximum compensation, due to rotation of the fispivoted memberupon which the spring acts. A further object. of the invention is toprovide a bearing surface for the load upon said pivoted member whichwill substantially avoid any horizontal component,v i. e., any componentdivergent from the line of pull of the load, i. e., which in everynormal position will be tangent to a line perpendicular to the line ofpull of the load at the point of contact.

In the drawings I ferred embodiment of have illustrated two pretheinvention and various modifications thereof, al1 designed to accomplishthese various objects, and which will serve to i1- lustrateithepractical application of the invention for the purpose of explaining itsprinciple and operation.

Fig. 1 is a side elevation of a preferred form of the invention;

Fig. 2 is a cross-section taken on line 2--2 of Fig. 1;

Fig. 3 is a cross-sectiontaken on line 3--3 of Fig. 1;

Fig. 4 is a longitudinal sectional view of the spring barrel shown indotted lines of Fig. 1;

Fig. 5 is a graph showing the moment of the spring` on the pivotedmember plotted against the angle at the pivot of said member dened bythe two points of pivotal connection of the spring;

Fig. 6 is a diagrammatic view similar to Fig. 1

showing an alternative type of compensating device;

Fig. 7 is a diagrammatic view similar to Fig. 1, showing still anotheralternative compensating device; i

Fig. 8 is a view in side elevation of another embodiment of theinvention;

Fig. 9 is a vertical section taken on line 9 9 ofFig. 8;

Fig. 10 is a vertical section taken on line 10-,10 of Fig. 7;

Fig.'11 is a side elevation of a pipe clamp suitable for use inconnection with the present invention;

Fig. 12 is` an end elevation of a. pipe clamp suitable for use inconnection with the present invention;

Fig. 13- is a side levation similar to Fig. a of Aanother preferred formof the invention; and Fig. 14 is a vertical section taken on line 14-14of Fig. 13.

Fig. 15 is a modied form of the device shown in Fig. 13.

Referring rst to Figs. 1 to 4, the device there illustrated comprises aframe 10 which may be vsupported by means of bolts 11, a horizontalshelf 12, and rollers not shown mounted on the frame by means of -bolts13. 'I'hese rollers are spaced from one or both of the bolts 11 soy asto permit substantial horizontal movement upon the shelf 12, and therebyto allow the support to adjust itself laterally to the line of pull oftheload.

A spring 15, which in thiscase is secured within a barrel 16 so as to'becompressed between the head 17 thereof and a movable head 18 secured tothe rod 19 by means of the nut 20, is' .anchored by means of trunnions21 in the nection of the end of the spring extends beyond the pivots 21,and whereas the opposite end of the springs fall short of the pivot 26,obviously this is immaterial, since for all practical purposes thepivots 26 and 21 are to be considered as the points of connection of thespring to the force-transmitting means 27 and the anchoring means 10,respectively, although the end of the spring which is connected to thepivot 26 through the bar 1Q is actually beyond the pivot 21, while theend which is connected to the p ivot 21 through the barrel 16 is midwaybetween the pivots 21 and 26.

The rod 19 is pivotally connected at 26 to the force-transmitting member27 which, in this case, is shown as a crank lever, and this lever, inturn, is pivoted on the frame 10, as shown at 28.

The load in illustrated in these figures is supported by a yoke 30which, as shown, may be connected through a turnbuckle 31 foradjustment, and through the ends of this yoke, is mounted a pin 32 whichpreferably carries a roller 33, and extends for a substantial distanceon ether side of the yoke so as to enter the slots 34 in the frame 10.The

sides of the cam slot 34 acting upon the pin 32l serve as a supplementalcompensation means by varying the moment arm of the load on the member27 to correct such variation in support as would otherwise remain.

A specially shaped cam 36 is provided as the bearing surface for theroller 33 on the forcetransmitting member 27, and in the present casethis is shown as removably positioned on the force-transmitting member27. This construc chosen merely for convenience.l

tion, however, is as I have preferred accurately to grind the cam block36 apart from the lever 27. Obviously, this could be integral instead ofseparable, as shown.

The surface of this block 36 is a slightly modied involute curve, but Ihave found it simplest and most satisfactory to use an empirical methodin its design. Paper models may be made to scale corresponding to thelever 27, to the frame with its slot 34 and to the roller 33, the blockportions 36 on the lever 27'being larger than required. These parts maybe mounted upon a drawing board and moved through the intended range ofoperation. Beginning with the pin 32 at one end of the slot 34, mark onthe model which represents the cam block 36 the point at which the lineof pull of the load intersects the circumference of the roller 33. Themodel representing the roller 33 and pin 32 is then moved a shortdistance at a time along the slot 3 4, and at each position of theroller the model representing the lever 27 is moved about the pivot 28until the last point thus marked is on the perpendicular to the line ofpull from its intersection'with the circumference of the roll 33. Thenev.7 point of intersection is then marked. When the opposite end of theslot has been reached. the points thus marked are joined in a smoothcurve which will be substantially the desired curve for the cam 36.

The curvature of the slot 34 may be determined in the following manner.With the particular spring and design, the required supplementalcompensation may be determined either mathematically or experimentally',and the the embodiment of my inventionl with the extension thus changein leverage, i. e., the perpendicular distance from the center of thepivot 28 to the line of pull of the load, from the point of tangencybetween the roller 32 and the block 36, may be calculated for the upperand lower limits of movement. This will give a centerV point as shown at32 and the points at the top and at the bottom of the slot 34, and withthese three points determined, an arc' is describedthrough them whichwill closely approximate the center line of the desired slot. Thevertical position of this slot is such that the pin 32 falls in thecenter of the slot when the force-transmitting member 27 is at thecenter of its normal movement.

Other types of supplemental compensation may be used; With the slot asjust described, the moment of the load upon the force-transmittingmember 27 is varied .byvshifting the load-carrying member 30 toward andaway from the pivot 28. A similar effect, however, can be obtained byvarying the moment of the spring upon the member 27 by shifting the rod19, `or the spring 15a if a long extension spring is used instead of thecompression spring 15 shown in Fig. 4, toward or away from the pivot 28.This I have illustrated diagrammatically in Fig. 7.

In Fig. 6, I have shown another alternative method of supplementalcompensation in which the pin 32 rides in a vertical slot 34a in theframe 10 to hold the load-carrying member 30 substantially along itsline of pull, .whereas a cam ,member 40 having a slot 41 for the pin 32is formed as part of an extension 22a of the adjusting slide 22 on eachside of the frame l0. A slot 43 for the pin 28 is preferably provided asan additional guide. Thus the movement of the' load serves to adjust thetrunnion 21, and theretension of the spring at dilerthe load so assubstantially to complete the compensation for variation in the momentwhich would be exerted by the spring` if not so adjusted.

In both the embodiments of Figs. 6 and 7, the slot 34a serves to controlthe leverage of the load upon the pivoted member 27 so as to maintain120 a constant moment arm, while the supplemental compensation affectsthe moment of the spring upon the member 27. The actual curvature will,of course, depend upon the characteristics of the spring, and theposition of the pivots 21, 26 and 125 28. With these factors determined,the curvature of the cam slot can be readily determined mathematicallyor, empirically. For example, with these factors xed, the extension ofthe spring required at each position 27 may be calculated for Fig. 7

=extension required where i M=Moment of the load on the member 27;P:=Perpendicular distance from pivot 28 to the line of pull of thespring for which extension is to be determined; 14C

F-:Force exerted by the spring in the position from which extension isto be measured;

K=Load/deflection ratio of the spring determined for each angularposition of the member 27, the shape of 14: the cam can be readilyplotted. f Figs. 6 and 7 are intended only as examples to emphasize thefact that the supplemental compensation is not limited to the particularmeans of the member 130 shown in Fig. 1, but that. any means responsivetto the movement of the load which varies either `tl1e tension of thespring or its mechanical advantage upon the load may serve to completethe compensation. g Nor are these modified forms recommended, ascompared with the preferred forms of Figs. 1, 8 and 13, since theyrequire more accurately machined cams and are subject to greaterfriction because of the pull of the spring on the cam follower againstthe cam face.

In all of these supports, it is to be understood,

of course, that friction will. introduce a variable error that is notsubject to correction. In speak- `ing of constant tension, compensation,balance, and correction, I preferto static conditions and recognizetheexistence of some variations due to friction. It is also recognized thatin practical construction,-the tolerances necessary in practicalmanufacture will cause errors, and for this reason, I prefer designssuch as shown in Figs. 1 to 4, 8, and 13, in which the effect of suchinaccuracies is In order that a given support of standard specifcationsmayy be used for a substantial range of loads, it is desirablto providefor adjustment to vary the location of the load upon the spring, andvice-versa. Such adjustment has already been described for the purposeof compensation t 1) by varying the moment arm of the l'oad on the lever27, (2) by Vvarying the moment arm of the spring upon the lever 27, and(3) by changing the initial tension of the spring, or, in other words,the point along its line of extension at which the spring begins toexert a tension. The last of theseI methods is preferred for adjustmentto the load when a design such as that shown in Figs. 1, 8, or 13 isadopted. since this adjustment will not interfere with the automaticcompensating adjustment. In Figs. 1 to 4, I have shown two methods ofaccomplishing such adjustment. In the first place, the initial tensionof the spring can be adjusted directly by means of the nut 20, and inthe second place, a similar adjustment may be made somewhat more easilyin cramped locations by means of a slideand bolt 22 to 24. vThe latterdoes vary slightly the triangle between the pivots 26, 28 and 21, andconsequentlythe moment arm at which the spring acts upon the lever 27 atany given position thereof, but is positioned and designed so that thisvariation is relatively unimportant.

I'he rails 23, in Figs. 1, 6 and 7 are so disposed that when the slide22 is moved, the axis of trunnions 21 follows a fixed straight linewhich passes through the axis of pivot 28. The reasons for this will bebetter understood by reference to Fig. 5.

lIn this figure, I have plotted the moment exerted by the spring 15 upon'the force-transmitting member'. 2,7 at the various angles measuredbetween the lines of centers 26-28 and 28-21. The curve which results issomewhat similar to a sinusoidal curve, resulting from the superimposingof the sine curve representingthe moment arm of the Aspring plottedagainst the angle 26-28-21 and the sine curve resulting from plottingthe tension or extension of the spring against the same angle. Thehorizontal axis on which the former curve is plotted is the center ofthe sine curve, whereas the latter curvev is tangent to the horizontalaxis, if the spring begins to act at the zero angle and is entirelyabove or extends below the axis, depending upon the point at which theaction of the spring begins. Since all negative values are imaginary andhave no .real existence in this latter curve, it will be disy continuousif the spring does not come' into action at the zero angle. The lattercurve, moreover, will have its maximum at 180, and its minimum at 0,whereas the former curve will have its maximum at 90 and its' minima at0 and 180, so that the resultant curve is a modified sine curve in whichthe right hand side of each node j is steeper than the left, and which,for a substantial distance near its maximum, is approximately flat. Thepositions of the pivots 26, 28, and 2l are chosen according to myinvention so that' the cente'r of the normal movement fallsapproximately at the maximum of this curve, and the range of normaloperation is substantially entirely along the flat portion of the curve.Thus, within this range, the variation from perfect balancing of theload by the spring and pivoted arm may be kept comparativelyslight.

These curves may be determined for any particular combinations ofspring. force-transmitting member, and other related parts, by measuringor calculating the moment arm and the force exerted by the spring at thesuccessive positions, calculating the moment and plotting against angle.I have found that with a support designed as illustrated herein, thespring is preferably chosen to bring the maximum of the curve in theneighborhood of 112, as illustrated by the curves b and c shown in Fig.5. The position of this maximum will depend upon the ratio of thedistances 21-28/26-28 between pivots and the initial length of thespring.

AAnother way of determining the design so as to assure operation alongthe flat maximum portion of the curve is as follows;v

Choose a convenient distance between the pivots 21-28 and a convenientlength between the pivots 26-28. I have found that a ratio of two toone, or three to one, between these distances is generally mostdesirable.

Choose an initial length for the spring. which should be such that thespring will be well within its limit of elasticity throughout itsoperating range, but will begin to be distorted before the operatingrange is reached. I have found that a very satisfactory initial lengthis two-thirds of the distance between the` pivots 26 and 21 when theangle 21-23-26 is at 90, i. e., an initial length such that the springwill be distorted onethird of its length when the arm 27 has been movedto the 90 position.

With these factors fixed, the moment arm and 'the extension of thespring in various angular positions of the arm 27 ar'e easily calculatedby 130 -ating range at this maximum angle.

The initial length of the spring,` has already been assumed, but thecharacteristic of the spring, i. e., thefload/deilection ratio, remainsto be determined. This will depend upon the load which is to besupported, andupon the moment arm at which 'the load acts'upon themember 27. When these are known, they are multiplied together to givethe moment'of the load on the 150 it arm 27, and since the moment of thespring must be the same in order to balance the load, the figure thusobtained is divided by the maximum value on the curve, already plotted(i. e., the moment which a spring with the load/deflection ratio of onewould exert), to give the required load/deflection ratio for the spring.Of course, if two springs are used, the characteristic thus calculatedwill be the combined characteristic of the two springs, and in fact, anynumber of springs or other resilient devices equivalent to springs canbe used in the same way. The above applies particularly to the case ofthe spring l5a, as shown in Figs. 8 and 13, or as it would be applied toFig. 1 in the manner illustrated in Fig. 7. Where the spring extendsbeyond the pivot 2l, as is situation may appear somewhat complicated,but if it is remembered that the spring 15, together with the parts 16'to 20, inclusive, is the equivalent of the spring 15a, and that thepoints of connection of this spring means are 26 and 21, this apparentcomplication will cause vno difflculty to those skilled in the art.

Grdinarily, for practical designs, I have found it best to choose theinitial length of the spring and the ratio of the distances 21--28 to26--28 so that the angle of maximum moment will fall in the neighborhoodof about to about 115, though these limits may be exceeded.

When the initial tension or precompression (or, stated in another way,the position of the member 27 at which the action of the spring begins)of the spring l5 is adjusted by moving the pivot 21 along the linebetween the pivots 21 and 28, the angle at which maximum moment isattained is changed only very slightly, and the range of operationcontinues to fall uponthe flat portion of the curve. Thus I have shownin Fig. 5 curves b and c resulting from adjustment in this way. rlhecurve a illustrates the case in which the spring is distorted from theinstant it leaves the dead center, or the zero angle position, and thecurves b and c illustrate cases in which the spring is relaxed sucientlyso that it does not begin to be distorted until a substantial angle isreached, about 45 in the case of curve c. The curve c may result fromthe curve b by the adjustment of the trunnion 21 alongthe line ofcenters between it and the pivot 28, or by other adjustment whichchanges the precompression or extension of the spring in the operatingrange without shifting the maximum of the curve to any great extent.

If adjustment should be effected by a shifting of the trunnion away fromthe line of centers, or otherwise adjusting the parts so that the anglebetween the linesof centers 26-28 and 28--21 at any given position ofthe load is altered by the adjustment, the maximum of the curve would beshifted laterally so that it occurs at a seriously dierent angle; andthis would throw the operating range of the parts over onto a steeperpart of the curve, where the compensation would be less complete.Particularly where a supplemental compensating means, such as the curvedslot 34 or the variations illustrated by Figs. 6 and 7, is used, itwould be objectionable thus to shift the operating range to a differentportion of the curve, because thereby the variations which call for thesupplemental compensation would be changed, and the supplemental meanswould no longer satisfactorily correct for the variations in momentexerted by the spring.

Although I have found the trunnion slide adthe case in Fig. 1 the ,ofthe duplication of slots resales justment 22, 23 24, particularlysatisfactory, I have in the construction illustrated in the drawingsshown an alternative adjustment which may be used instead of, or inaddition to, the ton adjustment. Thus the nut 20 may be adjusted alongthe :rod 19 so as to compress or relax the spring 15 within the barrel16, without moving the trunnions 21. The same eiect, of course, could beobtained by a shortening oi the rod 19 at any other point, e. g., by aturnbuclne beyond the barrel 16, or by ,an adjustment of the pivot 2e,or by the adjustment of the neas ri in the barrel I6. Numerous othermethods of adjustrnenty may be chosen, including methods o2 alteringmechanical advantage of the spring upon the load, as well as methods ofchanging the precompression of the spring, if it is remembered that theangle between the center lines 26.--28 and 28-21 is to be maintained,regardless ci the adjustment.

In Fig. 8 is shown another type of hanger which is particularlydesirable where a substantial space may bev provided between the loadand its support. In this case, a yoke bar 50 is secured to the I-beam51, or any other member upon which the load is to be carried, as forexample, by means of the hook clamp 52, in which the pivoted hooks aresecured over the flanges of the -beams by means of the bolt 53. Theframe 10a, in this case, is welded to the yoke bar 50 and secured to theclamp 52 by a bolt 54, which may be threaded at either or both ends toprovide adjustment. The force-transmitting members27a are, in this case,preferably duplicated so as to effect better balancing of forces on vtheframe 10a, and the springs 15a are, of course, also duplicated, and infact Ivhave found it preferable, for reasons of economy, to use twosprings side by side for each lever 27a, so that four springs in allwould beused for the support as shown in Fig. 8. Compression springs inbarrels may be used here, as in Fig. 1, but I prefer to use the springs15a as shown. At their upper ends, the springs are held by the bolts24a, which are adjustable along the line between the center vof thebearing portion of the spring eye 21a and a pivot 28a. In this case, asin the embodiment illustrated in Fig. 1,- the tension of the springs maybe adjusted by means of the bolts 24a, without substantially aecting theangle between the center lines 26a-28a and 28a-21a.

In this case, as in the embodiment illustrated in Fig. 1, I prefer toprovide upon the forcetransmitting members 27a bearing blocks 36, whichare shaped as already described in connectionwith Fig. 1. Slots34areprovided in the frame 10a for the same purpose as the correspondingslots already described in connection with Fig. l. In this case,however, the load-carrying yoke 30a is provided with horizontal slots 56which accommodate sidewise movement of the pins 32 carrying the rollers33, so that they may follow the contour of the cam` slots/34. Thesehorizontal slots 56 could, of course, be used in the construction shownin Figs. 1 to 4, but in that case are not necessary because the slighthorizontal movement of the load-carrying member 30 itself is notobjectionable. In this case, however, because 34 and pins 32, it isessential that relative movement in a horizontal direction be allowedbetween at least one of the pins 32 and the load-carrying member 30a. Itis furthermore of substantial advantage thus to relieve theload-carrying member from the necessity for bodily movement, and toallow it to act ros 'bolts 11, as shown in Fig. 1. Such lateralconsistently exactly along its une of pun. In this case, the adjustmentof the load-carrying mem-l ber to the position of the load is obtainedby .means of the adjusting nuts 31a, instead of by the turnbuckle asshown in Fig. 1. In this case,

yalso, we may provide, as shown inv Figs. l1 and 12, for any lateralmotion of the load by rollers 13a operating upon the shelf 12aassociated with the load-carrying member a, instead of the correspondingrollers associated with the support adjustment, however, is notessential.

It will be observed in Fig. 8 that the rollers 33 and the bearing blocks36 on .the pivoted arms 27a are positioned, when at the centers of theirnormal range of movement, so that the bearing points of the rollers 33upon the blocks 36 are substant tially on a horizontal line through thecenter of the pivot 28a, and the slots 34 are substantially along arcscentered on a horizontal line through the centers of the rolls 33 whenin said position. With this relation of the parts the moment of thefriction upon the arms 27a is kept at a minimum, and thereby the-errorwhich results therefrom is also minimized.

In Figs. 13 and 14, another simpler embodiment t of the invention isillustrated. In this case, the

frame 10b is required only to provide a rigid connection between theupper point ofsupport 21a for the spring, and the pivot point 28h, andof course to provide a connection to the point of support, e. g.,through a clamp 52 similar to that illustrated in Fig. 8. Theload-carrying member 30h is in this case essentially the same as thatillustrated in Fig.A 8, and the pivoted levers 27b are substantiallythesame as the levers 27 and 27a already shown and described, exceptthat in this case the bearing blocks 36 are omitted, and instead thepins 32h are secured directly to the levers 27b. The portion of thelever 27b which causes the pin 32D to follow an arc centered at the axis28h is therefore, in this case, the means for controlling the 4momentarm of the load on the lever 27b, and assumes, therefore, the functionof the corresponding controlling means in the other embodiment of theinvention,-namely the slots 34 and 34a. In order to minimize any errordue to friction, I prefer to mount the pins 32h in the levers 27b bymeans of anti-friction bearings, but except for the disadvantagesresulting from increased friction, these pins could be secured thereinmerely by means of set screws or pins, and allowed tol slide in theslots 56 of the load-carrying member 30a. The remainder of the devicemay be substantially identical with that illustrated in Fig. 8.

In Fig. 13, the slots 56 are made to accommodate normal movement of thelevers 27b, but to limit the movement beyond the normal range. Thus,even if the Asprings 15a should break (which is extremely unlikely tohappen, if a suflicient factor of safety is allowed in the choice of aspring) the load would not be completely dropped but the pins B2b wouldstrike the ends of the slots 56 at the bottom of the normal range, andthe member 30h would thereafter be rigidly supported upon the pins B2b.This means of limiting the movement of the load-carrying member is mostsimple and satisfactory where special provision is made for lateraladjustment, as shown, for example, at 12 and 13, or 12a and 13a, orWhere an angular adjustment of the entire device would not beobjectionable.

In Fig. 15, I have shown another way in which this may be simplyaccomplished, and at the same ing range of the lever 27b its principleand operation,

time provision may be made forlateral adjustment without thel use of anyseparate or supplemental device. In this case, the member A30e. is notcut out as shown in Fig. 13, but extends across the member 10b. A slot60 is provided` adjacent the vpivot 28e and the pivot 28e is extendedinto the slot 60.v The slot` 60.is of a width suicient to accommodatethe permissible lateral movement, and of a height suflicient toaccommodate the normal operating movements; and the slots 56a are, inthis case, 'madeen'ough longer than in the embodiment illustrated inFig. 13 so' as to accomvmodate the desired lateral movement. Uponhorizontalexpansion of a supported pipe, or lateral shifting, for anyother reason, of the load, the member 30o is moved laterally overthe`pins 32h, but otherwise the device will operate exactly as alreadydescribed in connection with Fig. 13. If, however, any extraordinaryconditionshould arise which would tend to move the member 30e beyond itspermitted operating range, the pin 28e would contact with the member 30eat the upper end of the slot 60, and the load would thereby be supporteddirectly upon the pin 28e, and through it upon the member 10b.

VIn the 'embodiment of Figs. 13, 14 and 15, the triangle dened by thetwo points of connection of the spring 26h and 21a and the pivot 28h isdesigned as already described, so that the operatwill fall on the flatportion of the moment-angle curve, vand will be approximately centeredat the maximum of said curve. The pins B2b are mounted on the levers 27bso that in their operation they describe an arc about the center 28b andthis arc is also chosen so that the maximum moment of the load 'isapproximately at the same position of the lever 27b as the maximummoment of the spring thereon,-that is, in the case shown, the linebetween the pivots 28b and 32B, when the lever 27b is at the maximum ofthe moment-angle curve, is perpendicular to the line of pull of theload. I have found that with the parts thus designed, the variation inthe moment of the load upon the armv 27b, due to the arcuate movement ofthe pin 32h, will effect substantially complete 'compensation for thevariation in moment of the spring upon the arm 27b, lso that thel forceexerted upon the load will remain substantially constant. thermore, Ihave found that the effect of friction is comparatively slightv when theparts are designed and constructed in the relation shown in Figs. 13 and14.

In all of these examples, the support is designed for a hanging load,but it will be apparent to those skilled in the art that the load may besupported Fur-V invention and certain modifications thereof, it is tovbe understood that these are given only as examples to aid inexplaining the invention and and that the invention is not in any waylimited to these particular forms. I

What I claim is:

1. An adjustable support comprising spring means, anchoring means towhich the spring means is pivotally connected, a pivotedforcetransmitting means pivotally connected to the opposite end'of thespring means, a load-carryting means, and a distortion of the of saidparts so as 2. Anadjustable support as defined in claim- 1, in which theadjusting means is adapted to vary the initial tension of said springlmeans while the line between the/pivot of the spring on the anchoringmeans and the pivot of the force-transmitting means on its supportremains substantially fixed.

3. An adjustable support as deiined in claim l, in which the means foradjusting the initial tension of the spring is adapted to shift thepivotal connection 'between the spring means and the anchoring meansalong the line between said pivotal connection and the pivot of theforcetransmitting means upon its support.

4. An adjustable support as defined in claim l, which includessupplemental compensating means adapted to correct for objectionablevariations in the force which would be exerted upon the load by saidspring without saidsupplemental means. l

5. A spring device comprising anchoring means, spring means secured tosaid anchoring means so as to permit angular movement of the springvabout the point of attachment, force-transmitting means connected to theopposite end of said spring so as to permit angular movementtherebetween and supported so as tol permit angular movement about itspoint of support, a load-carrying means bearing upon saidforce-transmitguide means adapted to control the 'moment arm of saidload-carrying means upon the force-transmitting means when the angularposition of the latter about its point of support is varied, and meansfor adjusting the spring while at any given position within its normalrange of movement, and While the line between the center of angularmovement of the spring relative to the anchoring means and the center ofmovement of the forcetransmitting means relative to its support remainssubstantially xed.

6. A support comprising' spring means, anchoring means to which thespring means is pivotally connected, a pivoted force-transmitting meanspivotally connected to the spring means, loadcarrying means connected tothe force-transmitting means, and means for varying the moment arm atwhich the load-carrying means acts upon the force-transmitting means soas to regulate the turning moment exerted upon said forcetransmittingmeans to correct any variation in the force which would be lexerted uponthe load if such correction were not made.

7. A support comprising spring means, anchoring means to which thespring means is pivotally connected, a pivoted force-transmitting meanspivotally connected to the spring means, loadcarrying means connected tothe force-transmitting means, and` means for shifting at least one ofthese points of connection upon the movement to regulate a turningmoment exerted upon said force-transmitting .means to correct anyvariation in the force which would be exerted upon the load if suchcorrection were not made.

8. A support as defined in claim 7, in which the correcting means is acam adapted to vary the leverage of the force-transmitting means on oneof the parts connected thereto.

necmss 9. An adjustable support as defined in claim '1, in which themeans for regulating a turning moment exerted upon theforce-transmitting means comprisesa cam surface adapted to shift thebearing point of the load on said force-transmitting means at the latteris moved, and thereby to vary the mechanical advantage of the springupon the load soy as to correct for objectionable variations in theforce which would be exerted upon the load by said spring without theeffect of said cam. t

10. A support as defined in claim '7, in which the correcting means isadapted to vary the moment arm of the load upon the force-transmittingmeans and the latter has a bearing surface for the load-carrying membershaped so that-in every normal position it is tangent to a linesubstantially perpendicular to the line of pull of the load at the pointof contact of the load-carrying v member thereon.

11. A support comprising spring means, anchor- -least one of saidmembers being adapted to vary the moment arm at which a force acts uponsaid pivoted member to compensate at least in part for the change intension of the spring means upon deformation of said spring when thepivoted member is moved, and the bearing surface of said pivoted memberupon which the load-carrying member is supported being shaped so that itis always tangent to the load-carrying member and at the same point to aline substantially perpendicular to the line of pull of the load.

l2. A spring device comprising anchoring means, spring means secured tosaid anchoring means so as to permit angular movement of the springabout the point of attachment, a forcetran'smitting member connected tothe opposite end of said spring so as to permit angular movementtherebetween and supported so as to permit angular movement about itspoint of support, a load-carrying member slidably connected to saidforce-transmitting"member, and a guide means adapted to control theradial position of said load-carrying member upon the force-transmittingmember when the angular position of the latter is varied, and in whichthe bearing surface n of the force-transmitting member upon which theload-carrying member is supported comprises a cam shaped to present atevery position within the normal range of movement of said parts asurface tangent to the portion of the load-carrying member which bearsthereon, and tangent at the same point to a line substantiallyperpendicular to the direction of pull of the load.

13. A spring ldevice as defined in claim 12, in which the guide means isadapted to vary the perpendicular distance of the direction of pull ofthe load from the center of angular movement of the yforce-transmittingmember relative to its support, and thereby to change the turning momentof the load upon said force-transmitting i the parts relative to eachother ing means to which the spring means is pivotally connected,pivoted force-transmitting means pivotally connected to the opposite endof the spring means, a load-carrying means supported fromforce-transmitting means, the pivots between the spring and anchoringmeans, between spring means and force-transmitting means, and betweenforce-transmitting means and its support,

-being positioned so that in approximately the center of its normaloperating range the spring means will exert a maximum turning momentupon the force-transmitting means.

16. A spring y device comprising anchoring means, spring means securedto said anchoring means so as to permit angular movement of the springabout the point of attachment, a forcetransmitting means connected tothe opposite end of said spring so as to permit angular movementtherebetween and supported so as to permit angular movement about itspoint of support, a load-carrying means slidably connected to saidforce-transmitting means, and a means adapted to control the moment armo f said load-carrying means upon the force-transmitting means when theangular position of the latter about its point of support is varied, inwhich device the spring and its anchoring means are so related to theforce-transmitting means that when near the centers of their normalranges of movement, the spring produces a maximum turning moment on theAforce-transmitting member.

17. A spring device as defined in claim 16, in which the bearing surfacefor the load-carrying means on the force-transmitting means is near aline perpendicular to the line of pull of the load at the center ofangular movement of the force-transmitting means relative to itssupport.

18.` A support comprising spring means, an,

choring means to which the springmeans is connected, pivotally supportedforce-transmitting means connected to the spring means,'load-carryingmeans supported upon said force-transmitting means, and means forcontrolling the moment arm at which the load acts upon theforce-transmitting means, the bearing surface for said load-carryingmeans upon the forcetransmitting means being, when at the center of itsoperating range, near a line perpendicular from the axis of the pivot ofthe force-transmitting means to the line of pull of the load.

19. A support comprising spring means, anchoring means to which thespring means is pivotally connected, pivoted force-transmitting thespring means so that the moment of the spring on said force-transmittingmeans is at a maximum near the center of its operating range,load-carrying means supported from the forcetransmitting means, andmeans for varying the moment arm of the load upon the force-transmittingmeans so that said load a'cts thereon at approximately its maximummoment arm, near the center of its normal operating range.

20. A support as defined in claim 19, in which the means for varying themoment arm of the load-carrying means upon the force-transmitting meansis an arm connected to the forcetransmitting means so as to rotatetherewith, and to which arm the load-carrying means is pivotallyconnected, and which is positioned so that at the center of itsoperating range the line through its two pivots is approximatelyperpendicular to the line of pull of the load.

21. A support comprising spring means, anchoring means to which thespring means is pivotally connected, pivoted force-transmitting meanspivotally connected to the opposite end .of the spring means,load-carrying means, and an arm connected to the-force-transmittingmeans to rotate therewith, and adapted to forni a pivotal support forthe load-carrying means, said load-carrying means and said arm beingpositioned relative to thepulls of the spring and of the loadrespectively, so that the moments of lthe spring and of the load thereonreach their maximums at approximately the same position of saidload-carrying means.

22. A spring device comprising a pair of pivotally supportedforce-transmitting members pivoted about the same axis, springspivotally supported at one end, and pivotally connected to saidforce-transmitting means at their other ends, a pin rotatably mounted ineach of the force-transmitting members at substantially the samedistancefrom the common pivot and circumferentially positioned about said pivotso that at approximately the center of their normal range of movementboth will fall upon the diameter through the common pivot perpendicularto the line of pull of the load, and a load-carrying member havingbearing surfaces for said pins substantially perpendicular to the lineof p ullof the load, and of suicient length to accommodiate lao

